We’ll get into some detail later, but for a baseline—
• 1 rem received in a short period or over a long period is safe—we don’t expect observable health effects.
• 10 rem received in a short period or over a long period is safe—we don’t expect immediate observable health effects, although your chances of getting cancer might be very slightly increased.
• 100 rem received in a short time can cause observable health effects from which your body will likely recover, and 100 rem received in a short time or over many years will increase your chances of getting cancer.